Bug or feature?

I recently experienced a problem trying to confirm a newly slotted skirmish trait. During the second half of the skirmish training, "Defense of the Prancing Pony", I purchased the Warrior trait from Will, but when I tried to slot it with Tom the Confirm button remained greyed out. This had never happened before. I logged out, logged in, same thing. I waited until the next day, same thing. I finally submitted an in-game bug report. The GM was very nice and told me the traits in my character's trait tree was blocking my ability to click the Confirm button for my skirmish solder. I thought that was weird, but did as instructed and re-specialized my trait tree, removing all traits. Sure enough, this solved the problem. After slotting the Warrior trait I retraited my character and completed the skirmish.

Today another character attained 25th level. I immediately went to the skirmish camp to change the skirmish soldier race. Sure enough, the Confirm button remained greyed out. I had to re-specialize once again, this time paying silver for the privilege, before I could slot the race.

Now, I figured this was a major bug until I remembered a one line note in the U14 release notes: "You can no longer slot a conflicting set of skirmish traits." I have no idea what that means unless it means you cannot slot skirmish traits without unslotting all character traits.

My question to the community: Is this a bug or a feature? The GM did not mention anything about this being a bug, so I have to wonder.